The present invention relates to an apparatus and method for shielding X-rays that are generated when a sample to be measured is analyzed by using radiation, and more particularly, to a radiation shielding apparatus and method for preventing the radiation from leaking from a radiation fluorescent analyzing device.
In general, radiation fluorescent analyzing device is a kind of non-destructive analyzing device for obtaining information in regard to atom and electron structures such as industrial materials, i.e., semiconductor materials, catalysts, and amorphous materials.
Typically, the radiation fluorescent analyzing apparatus usually uses X-rays that are a kind of radiation. Hereinafter, the X-ray fluorescent analyzing device will be described in detail as an example.
In the X-ray fluorescent analyzing device, the X-rays are irradiated to a sample, and then energy of a fluorescent photon that is generated from the sample is detected to analyze the sample.
That is, the X-rays used for the X-ray fluorescent analysis correspond to fluorescent X-rays having energy of about 25 KeV or less. Here, energy of the fluorescent photon that is radiated from an object to be measured (hereinafter, referred to as a “measurement object”) to which the X-rays are absorbed may be detected to measure elementary composition of the measurement object.
The principle of X-ray generation in an X-ray tube is as follows. Broad-band x-rays are generated to correspond to an anode voltage of first fluorescent x-rays that are generated from a target in the tube. Usually, since silver (Ag) generates specific radiation of about 24 KeV or less, when an anode voltage of about 35 KVp is applied to the silver (Ag), X-rays of about 3 KeV to about 35 KeV may be generated.
Also, the generated X-rays travel at an angle of about 180° with respect to an anode surface. Here, the X-rays are radiated in the form of electromagnetic waves with respect to a reflection angle corresponding to an incident angle of the incident electron beam to travel in parabolic distribution.
The generated X-rays may be shielded except for a portion thereof toward the sample by a collimator. Here, only a portion of the X-rays may be transmitted to correspond to an area to be irradiated of the sample. Thus, the X-rays are not scattered by mechanisms around the sample to unaffect the measurement.
The X-rays incident into the sample dislodge an orbital electron of each of the elements composing the sample or excites an orbital electron of each of the elements composing the sample to a high energy level, thereby losing energy thereof. Here, X-rays having a specific wavelength generated due to energy differences between orbits of the electron while the electron is transited from a relatively high orbit to a relatively low orbit is radiated, and the X-rays are called characteristic X-rays.
Also, the energy of the generated characteristic X-rays is classified by an element, distribution of the energy generated from the electron orbits K, L, and M is measured in a spectrum manner to quantitatively and qualitatively measure the measurement object.
Thus, the radiation fluorescent analyzing device for quantitatively and qualitatively measuring the measurement object by using the radiation such as the X-rays needs a shielding apparatus that is capable of efficiently shielding the radiation.
An example of the X-ray shielding apparatus according to the related art is disclosed in Korean Patent Application No. 10-2012-0026833, titled “Fluorescent X-ray Analyzing Shielding Apparatus”.
According to the related art disclosed in Korean Patent Application No. 10-2012-0026833, there is provided a fluorescent X-ray analyzing shielding apparatus including: a shielding box; a first door slid on the shielding box; a sample holder disposed on a lower end of the first door, wherein the shielding box includes an acryl plate, a lead-glass plate formed on the outside of the acryl plate, and an aluminum plate formed on the outside of the lead-glass plate, a partition wall is disposed in the shielding box, and a second door is openably disposed on the partition wall.
According to the related art, fluorescent X-rays generated by irradiating X-rays that are radiated from a radioactive isotope onto the sample are measured by an X-ray spectrometer. Then, a frequency of an energy area of each of components by analyzing a spectrum is used to obtain a component content in the irradiated sample. Thus, the fluorescent X-ray analyzing shielding apparatus is provided so as to perform the analyzing process within the safe shielding box. The sample is seated in the fluorescent X-ray analyzing shielding apparatus, and the X-ray fluorescent analyzing device operates only in a state where all doors are closed to prevent the radiation from leaking to the outside. Also, a distance between the sample and a radiation source irradiating the radiation onto the sample may be adjusted in a state where the shielding box is closed to easily analyze the sample.
On the other hand, according to the related art, it is difficult to recognize operation states of various devices in the shielding box from the outside, and thus a user may not easily recognize whether the radiation leaks from the outside.
Also, in order to operate the radiation generating device within the shielding box, a power supply line has to be connected to the radiation generating device. Thus, the shielding box needs a line through-hole. Therefore, the radiation may leak through the through hole.